Plant-Based Diets, Lignan Intake, Weight Change, and the Risk of Gout

Abstract

Background: Gout is the most common inflammatory arthritis that predominantly affects adult men and postmenopausal women. In parallel with the rising prevalence of gout, the burden of obesity has more than doubled globally in the last several decades. Growing evidence suggests that both gout and obesity development may be in part modulated by endogenous estrogens. Dietary lignans, which naturally occur in plant foods, are of particular interest as they undergo metabolism by the gut microflora to form bioactive enterolignans which can then bind estrogen receptors. The objectives of this dissertation were to prospectively examine: 1) whether three plant-based diet indices are associated with incident gout; 2) whether dietary lignan intake is associated with incident gout; and 3) the relation between dietary lignan intake and weight change.

Methods: We used data from three large ongoing prospective cohort studies: the Health Professionals Follow-up Study, the Nurses’ Health Study (NHS), and the NHS2. Every 2-4 years, participants provided detailed data on usual dietary intake and self-reported their weight and other lifestyle information. We used Cox proportional hazards regression models and generalized linear regression models to examine the associations of interest.

Results: We found that a healthful plant-based diet was significantly inversely associated with gout while an unhealthful plant-based diet was positively associated with gout. We additionally found significant inverse associations between whole grains, tea/coffee, and dairy products with gout. Among less healthful plant foods, fruit juices and sugar-sweetened beverages were both positively associated with gout. When we examined lignan intake, we found significant inverse associations between both matairesinol and secoisolariciresinol, but did not observe any relationship with pinoresinol or lariciresinol. In our analysis of lignan-rich foods items, we found that greater consumption of whole grain cold breakfast cereal, cooked oatmeal, and added bran were associated with a lower risk of gout. Finally, we found that increases in total lignan intake (and all four major individual lignans) were associated with less weight gain during the same period.

Conclusions: Taken together, our findings support current dietary recommendations to eat a healthy plant-based diet and suggest that selecting food items that are rich in lignans (such as whole grains, fruits, vegetables, and flaxseed) may be beneficial for reducing gout risk and promoting weight control.